The valve of this invention is a safety valve which is used, for example, between a gas cylinder of gas at very high pressure and the inlet of a pressure regulator. It is also used, or it can be used, in the low-pressure delivery line from a pressure regulator to a system using gas at the regulated pressure. In each instance the valve of this invention is used to shut off automatically the flow of gas when the flow exceeds some predetermined rate.
Whether used between a cylinder of high pressure gas and a pressure regulator inlet or used beyond the pressure regulator, the valve of the invention senses the flow as an interposed pressure drop and, when the preset differential pressure limit is exceeded, closes with a snap action, preventing flow by making a leak-tight seal.
The problem to which the invention is directed is therefore primarily that of preventing accidents and damage to equipment resulting from excessive flow of gas under pressure.
It is also important, of course, to be able to resume flow, and the invention makes it very simple to do that.
Other objects and advantages of the invention will become apparent from the following description.